This invention relates to an eye refractometer for measuring an eye refractivity without judging for a patient.
Heretofore, there is known an apparatus for measuring eye refractivity, wherein a measuring target is projected to the retina of an eye under test through two points on a pupil of the eye under examination. The target is separated along a predetermined meridian direction with respect to the eye under test to form the so-called split target image. Refractivity of the meridian direction is measured by separating a quantity of the split target image at the bottom of the eye under test, such measurement being carried out in each of at least three different meridian directions. Based on the foregoing result, spherical power, astigmatism power and astigmatism axis angle of the eye under test is determined.
However, in the conventional eye refractometer, only after at least three separate measurements of refractivity in the meridian direction are carried out, may spherical power, astigmatism power and astigmatism axis angle of the eye under test be determined. Accordingly, the refractivity cannot be measured in a short time. Moreover, the measuring target is required to be movable to be generally focussed on the retina of the eye in order to form a split target image. Thus, the construction thereof is inevitably complicated.
The present invention was developed in view of the above mentioned problems inherent in the prior art.